Which Threat to Internal Validity Is Most Likely to Affect

question 88

Multiple Choice

Which threat to internal validity is most likely to affect an experiment in which one of the conditions is very unpleasant or demanding?

• A) Mortality
• B) History
• C) Selection
• D) Interactions with selection

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Definitions:

Facial Nerve

The seventh cranial nerve that controls the muscles of facial expression, taste sensation on two-thirds of the tongue, and the production of saliva and tears.

Trigeminal Nerve

A cranial nerve responsible for sensory information from the face and motor functions such as biting and chewing.

Pyramidal System

A motor system that carries voluntary movements signals from the brain to the muscles, mainly involving the cerebral cortex and the spinal cord.

Corticospinal Tract

A set of nerve pathways that travel from the cerebral cortex in the brain down the spinal cord, involved in controlling voluntary muscle movements.